M. Hoshi et al. / Tetrahedron Letters 48 (2007) 119–124
123
Chem. Eur. J. 2000, 6, 2044–2052; (e) Schwab, P. F. H.;
Smith, J. R.; Michl, J. Chem. Rev. 2005, 105, 1197–1279,
and references cited therein.
313 (10), 202 (13). HRMS (EI) Calcd for C26H18 (M+):
330.1409. Found: 330.1417.
13. Negishi, E.; Williams, R. M.; Lew, G.; Yoshida, T. J.
Organomet. Chem. 1975, 92, C4.
2. (a) Bumm, L. A.; Arnold, J. J.; Cygan, M. T.; Dunbar, T.
D.; Burgin, T. P.; Jones, L., Jr.; Allara, D. L.; Tour, J. M.;
Weiss, P. S. Science 1996, 271, 1705–1707; (b) Chen, J.;
Reed, M. A.; Rawlett, A. M.; Tour, J. M. Science 1999,
286, 1550–1552; (c) Donhauser, Z. J.; Mantooth, B. A.;
Kelly, K. F.; Bumm, L. A.; Monnell, J. D.; Stepleton, J. J.;
Price, D. W., Jr.; Rawlett, A. M.; Allara, D. L.; Tour, J.
M.; Weiss, P. S. Science 2001, 292, 2303–2307.
3. Dai, C.; Nguyen, P.; Marder, T. B.; Scott, A. J.; Clegg,
W.; Viney, C. Chem. Commun. 1999, 2493–2494.
4. For examples, see: (a) Bunz, U. H. F. Chem. Rev. 2000,
100, 1605–1644, and references cited therein; (b) Schmitz,
C.; Po¨sch, P.; Thelakkat, M.; Schmidt, H.-W.; Montali,
A.; Feldman, K.; Smith, P.; Weder, C. Adv. Funct. Mater.
2001, 11, 41–46; (c) Anderson, S. Chem. Eur. J. 2001, 7,
4706–4714.
5. Levitus, M.; Schmieder, K.; Ricks, H.; Shimizu, K. D.;
Bunz, U. H. F.; Garcia-Garibay, M. A. J. Am. Chem. Soc.
2001, 123, 4259–4265.
6. Beeby, A.; Findlay, K.; Low, P. J.; Marder, T. B. J. Am.
Chem. Soc. 2002, 124, 8280–8284.
7. Meier, H. Angew. Chem., Int. Ed. Engl. 1992, 31, 1399–
1420, and references cited therein.
8. (a) Hoshi, M.; Shirakawa, K. Synlett 2002, 1101–1104; (b)
Hoshi, M.; Kawamura, N.; Shirakawa, K. Synthesis 2006,
1961–1970.
14. General procedure for the preparation of 6: To a solution of
disiamylborane (4 mmol) in THF (12 mL) was added 1-
iodo-2-phenylethyne (0.912 g, 4 mmol) dropwise at
À15 ꢁC under argon, and the reaction mixture was stirred
for 2 h at 0 ꢁC. A solution of 1 M LiBEt3H (4 mL,
4 mmol) in THF was added dropwise to a stirred solution
of (Z)-1-iodo-2-phenylethenyldisiamylborane, thus pre-
pared, in THF at À25 ꢁC, and the mixture was allowed
to warm gradually to room temperature over 1 h. Et3B,
liberated from LiBEt3H, was removed under reduced
pressure, accompanied by the solvent. After the addition
of THF (12 mL) to the residue under argon, the resulting
solution of 2a in THF was subjected to the reaction
process as described in the general procedure for the
preparation of 5. Compound 6a [eluent: hexane/CH2Cl2
1
(9/1)]: mp 119–121 ꢁC. IR (KBr): 833, 788, 688 cmÀ1. H
NMR (500 MHz, CDCl3): d 5.93 (d, 2H, J = 11.7 Hz),
6.73 (d, 2H, J = 11.7 Hz), 7.25–7.44 (m, 6H), 7.46 (s, 4H),
7.91 (d, 4H, J = 7.3 Hz). 13C NMR (125 MHz, CDCl3): d
90.3 („C · 2), 95.4 („C · 2), 107.2 (@CH · 2), 123.4
(@C · 2), 128.3 (@CH · 4), 128.7 (@CH · 2), 128.8
(@CH · 4), 131.4 (@CH · 4), 136.5 (@C · 2), 139.2
(@CH · 2). EIMS: m/z (%) = 330 (M+, 100), 329 (18),
328 (26), 327 (33), 326 (32), 313 (16), 226 (10), 202 (23),
163 (15).
9. Hoshi, M.; Nakayabu, H.; Shirakawa, K. Synthesis 2005,
1991–2007.
15. Compound 5c [eluent: hexane/CH2Cl2 (9/1)]: mp 71–73 ꢁC.
IR (KBr): 950, 746, 688 cmÀ1 1H NMR (500 MHz,
.
10. The preparation of conjugated compounds containing
bis(alk-3-en-1-ynyl)benzene unit has been reported, see:
Venkatesan, D.; Yoneda, M.; Ueda, M. React. Funct.
Polym. 1996, 30, 341–352.
11. (a) Brown, H. C. Organic Syntheses via Boranes; Wiley-
Interscience: New York, 1975; (b) Matteson, D. S.
Stereodirected Synthesis with Organoboranes; Springer:
Berlin, 1995.
CDCl3): d 6.47 (d, 2H, J = 16.1 Hz), 7.13 (d, 2H,
J = 16.1 Hz), 7.24–7.35 (m, 8H), 7.42 (d, 4H, J = 6.8 Hz),
7.48 (dd, 2H, J = 5.8, 3.4 Hz). 13C NMR (125 MHz,
CDCl3): d 90.6 („C · 2), 93.2 („C · 2), 108.2 (@CH ·
2), 125.8 (@C · 2), 126.4 (@CH · 4), 127.9 (@CH · 2),
128.7 (@CH · 2), 128.7 (@CH · 4), 131.8 (@CH · 2), 136.3
(@C · 2), 141.8 (@CH · 2). EIMS: m/z (%) = 330 (M+, 90),
329 (42), 328 (28), 327 (33), 326 (41), 324 (11), 315 (12), 314
(10), 313 (22), 302 (16), 300 (16), 289 (10), 253 (39), 252 (71),
251 (15), 250 (45), 248 (11), 239 (38), 237 (17), 226 (27), 225
(12), 224 (19), 216 (19), 215 (100), 213 (21), 202 (12), 200
(12), 150 (10), 115 (20), 91 (18), 78 (12), 77 (19).
12. General procedure for the preparation of 5: To a stirred
solution of 1a (4 mmol) in THF (12 mL) at À15 ꢁC,
Cu(acac)2 (0.052 g, 0.2 mmol) was added under an argon
flow, followed by dropwise addition of (trimethyl-
silyl)ethynyl bromide (0.474 g, 2.68 mmol) and 1 M
NaOMe (3 mL, 3 mmol), and the resulting mixture was
allowed to warm gradually to room temperature and
stirred overnight. The mixture was cooled to 0 ꢁC, and
PdCl2(dppf)ÆCH2Cl2 (0.033 g, 0.04 mmol) and CuI
(0.015 g, 0.08 mmol) were added to the cooled mixture
under an argon flow followed by dropwise addition of n-
Bu4NOH (40 wt% solution in H2O) (2.66 mL, 4 mmol)
and diiodobenzene (0.66 g, 2 mmol). After stirring for 4 h
at room temperature, the reaction mixture was treated
with 3 M NaOH (4 mL) and H2O2 (30 wt% solution in
H2O) (2 mL) at 0 ꢁC and stirred for 1 h at the same
temperature to decompose the residual organoboron
compound. The resultant mixture was extracted with
ether, washed with brine, dried over anhydrous Na2SO4,
and concentrated under vacuo. Purification by column
chromatography on aluminum oxide (Merck aluminum
oxide 60 active basic) provided product 5. Compound 5a
[eluent: hexane/CH2Cl2 (9/1)]: mp 193–196 ꢁC. IR (KBr):
16. Compound 5b [eluent: hexane/CH2Cl2 (9/1)]: mp 117–
119 ꢁC. IR (KBr): 950, 794, 748, 688 cmÀ1 1H NMR
.
(500 MHz, CDCl3): d 6.38 (d, 2H, J = 16.1 Hz), 7.05
(d, 2H, J = 16.1 Hz), 7.25–7.37 (m, 7H), 7.39–7.45 (m,
6H), 7.58 (br s, 1H). 13C NMR (125 MHz, CDCl3):
d
89.5 („C · 2), 90.9 („C · 2), 107.9 (@CH · 2),
123.8 (@C · 2), 126.4 (@CH · 4), 128.5 (@CH), 128.8
(@CH · 6), 131.1 (@CH · 2), 134.4 (@CH), 136.2
(@C · 2), 141.7 (@CH · 2). EIMS: m/z (%) = 330 (M+,
100), 329 (20), 328 (24), 327 (29), 326 (27), 313 (15), 250
(12), 226 (11), 203 (10), 202 (24), 163 (13), 69 (11).
Compound 6b [eluent: hexane/CH2Cl2 (9/1)]: mp 93–
95 ꢁC. IR (KBr): 781, 688 cmÀ1 1H NMR (500 MHz,
.
CDCl3): d 5.92 (d, 2H, J = 11.7 Hz), 6.73 (d, 2H,
J = 11.7 Hz), 7.25–7.45 (m, 9H), 7.59 (s, 1H), 7.91
(d, 4H, J = 7.8 Hz). 13C NMR (125 MHz, CDCl3): d
88.9 („C · 2), 94.8 („C · 2), 107.1 (@CH · 2),
123.9 (@C · 2), 128.4 (@CH · 4), 128.6 (@CH), 128.6
(@CH · 2), 128.8 (@CH · 4), 131.3 (@CH · 2), 134.1
(@CH), 136.4 (@C · 2), 139.2 (@CH · 2). EIMS: m/z
(%) = 330 (M+, 100), 329 (21), 328 (24), 327 (30), 326 (30),
313 (16), 250 (11), 202 (21), 163 (10), 69 (17).
17. The fluorescence intensity of 5a was about 60% of that of
6a.
1
956, 840, 748, 690 cmÀ1. H NMR (500 MHz, CDCl3): d
6.39 (d, 2H, J = 16.1 Hz), 7.05 (d, 2H, J = 16.1 Hz), 7.26–
7.37 (m, 6H), 7.42–7.45 (m, 8H). 13C NMR (125 MHz,
CDCl3): d 90.9 („C · 2), 91.5 („C · 2), 107.9 (@CH · 2),
123.1 (@C · 2), 126.4 (@CH · 4), 128.8 (@CH · 6), 131.4
(@CH · 4), 136.2 (@C · 2), 141.7 (@CH · 2). EIMS: m/z
(%) = 330 (M+, 100), 329 (15), 328 (20), 327 (24), 326 (22),
18. The fluorescence intensity of 5c was below 2% of that of
6a.